PAM2301

Document number: DS36384 Rev. 3 - 2

10 of 13

www.diodes.com

February 2018

© Diodes Incorporated

PAM2301

100% Duty Cycle Operation

As the input voltage approaches the output voltage, the converter turns the P-Channel transistor continuously on. In this mode the output voltage

is equal to the input voltage minus the voltage drop across the P-Channel transistor:





R

R

I

V

V

L

)

ON

(

DS

LOAD

IN

OUT









UVLO AND Soft-Start

The PAM2301 has an internal soft-start circuit that limits the in-rush current during start-up. This prevents possible voltage drops of the input

voltage and eliminates the output voltage overshoot. The soft-start acts as a digital circuit to increase the switch current in several steps to the

P-Channel current limit (1500mA).

Short Circuit Protection

The switch peak current is limited cycle-by-cycle to a typical value of 1500mA. In the event of an output voltage short circuit, the device operates

with a frequency of 400kHz and minimum duty cycle, therefore the average input current is typically 200mA.

Thermal Shutdown

When the die temperature exceeds +150°C, a reset occurs and the reset remains until the temperature decrease to 120°C, at which time the

circuit can be restarted.

PCB Layout Check List

When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the PAM2301. These items are

also illustrated graphically in Figure 1. Check the following in your layout:

1. The power traces, consisting of the GND trace, the SW trace and the VIN trace should be kept short, direct and wide.

ground.

4. Keep the switching node, SW, away from the sensitive VFB node.

5. Keep the (

Figure 1. PAM2301 Suggested Layout